SDR# with rtl-sdr.com dongle v3 not changing frequency / freeze

[JayMore]

I received my RTL-SDR.COM v3 a few days ago, and now i'm playing with it.
I tried different SDR software, and SDR-Sharp seems the best, but I experience two majors problems (Windows 7 32b) :
- Freezing : from time to time, I cant quit SDR#, or click on the STOP button. The application is frozen, I have to kill it with the task manager.
- Frequency not changing : When I tune to a frequency, the tuner is not really changing. SDR# reflect the frequency change on the digit, but the waterfall or the wave display still show the old frequency, and I stil listening to the old freq. I have to wait several seconds (sometime more than 10s) for the graphic to be updated and the frequency to be really changed.

I tried different USB port (I only have 4 ports on my laptop), and same things.

I sample at 250Khz in SDR#, no direct sampling on frequency, but I always got the same behavior. After a few minute of running (I would say, 15mn listing on 443 Mhz for example), I cant close the program or stop listing without having to kill it, and frequency change take so long to be reflected. I only have standard SDR# plugins.

The freezing do not happends with other SDR software (HDSDR), but I have the same prb of frequency change with HDSDR.

[rtlsdrblog]

What are your PC specs? On an older laptop I sometimes find that SDR# can lag and get stuck. It's just a bit more CPU intensive compared to older software like HDSDR.

[JayMore]

It is a DELL 640M laptop (always plugged to AC), W7 32b, 2GB of RAM, Intel core duo T2050 1,6GHz. Quite old (more than 10 years!).
I also noticed same behavior (freeze / frequency stuck) with the rtl_tcp driver, with the dongle connected on a Raspberry in the same network.
This kind of lag can be, for sure, because the PC is old, but I do not have a stronger PC to compare.